Learn more about Under the Red Sun:

An alien ship, orbiting the Earth, sets up a screen to filter sunlight. Red radiation hits the planet and the Man of Steel''s superpowers begin to drain away. Who will save Earth from the coming invasion of alien warriors?

From the Publisher:When an alien ship sets up a giant filter to turn the Sun's rays red, a scheming alien plans on taking advantage of Superman's weakened state in the absence of yellow sunlight by leading an invasion of the earth.